<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>hogwarts</title>
    <style>
        h1 {text-align:center;}
        table
        {
            border-collapse:collapse;
        }
        table,th,td{
            border:1px solid black;
        }
        table
        {
            width:100%;
        }
        th
        {
            height:50px;
        }
        td
        {
            height:50px;
            vertical-align:bottom;
        }
        table, td, th
        {
            border:2px solid black;
        }
        th
        {
            background-color:blue;
            color:white;
        }
        tr:hover{
            background:#FFFF85;
        }
        body {background-color:#b0c4de;}
    </style>
</head>
<body>
    <h1>用户列表</h1>
<table>
    <tr>
    <th>用户名</th>
    <th>性别</th>
    <th>年龄</th>
    </tr>
    <tr>
        <td>张三</td>
        <td>男</td>
        <td>19</td>
    </tr>
    <tr>
        <td>李美丽</td>
        <td>女</td>
        <td>23</td>
    </tr>
</body>
</html>